JPH0213073B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a calender roll structure, and in particular has a drilled heat medium passage near the surface of the outer cylindrical roll so that the roll surface is heated by the heat medium introduced from the end of the roll. Regarding the calendar roll structure made.

In calender rolls, the quality of the product is generally mainly influenced by roll run-out accuracy during heating time, thermal responsiveness in the roll effective surface length, uniformity of temperature distribution, and the like. In addition, from the standpoint of energy conservation, the time required to raise and lower the roll temperature can be shortened, and in order to smoothly start and stop frequently, rolls with a small heat capacity and little flywheel effect are required. .

As conventional rolls for this type of calender, for example, hollow assembly rolls made of chilled cast iron, which are relatively low cost and easily available, as shown in FIG. 1, have been mainly used. However, such a hollow assembly roll has a problem with the temperature distribution of the roll due to its hollow structure, and in particular, in the figure, the heating effect by the heating medium (the direction is indicated by an arrow) supplied to the hollow roll 1 is The roll ends 1A, 1B are uneven in the longitudinal direction.
The effective surface length of the roll is restricted because the temperature drop is significant. In addition, due to the hollow structure, the roll bearing parts 2A, 2
Since it is necessary to take into account the deflection error of the roll that occurs between B and the like, the wall thickness cannot be made sufficiently thin, which reduces thermal response and makes it easier for temperature differences to occur on the effective surface of the roll during work. .

In addition, for this type of structure, for example,
As described in Japanese Patent No. 51895, there is a double-tube structure with a drum inside. However, even with this structure, there is a drawback that a temperature gradient tends to occur across the roll surface from left to right as a result of heat exchange with the material to be formed, similar to the conventional example described above. In addition, in order to maintain good thermal response by reducing the thickness of the roll, it is necessary to separately provide a mechanism for adjusting the deflection that occurs in the roll, and furthermore, in this example, the heating medium remains inside the drum. Therefore, when controlling the rise and fall temperature of the roll, it is necessary to control not only the roll itself but also the stagnant heating medium.
As a result, there is a drawback that thermal responsiveness is reduced and more thermal energy is required.

On the other hand, as shown in Fig. 2, a heating medium passage 4 is bored near the surface of the solid roll 3, and the heating medium is circulated through a supply/discharge pipe 5 to heat the roll surface. Drill dolls are also used. With this roll, the heat medium is effectively supplied to the heat medium passage 4 near the surface of the roll, so the roll temperature distribution is better than that of a hollow roll, and the heat transfer area is more than double, so the heat transfer area is more than double. The physical characteristics are also significantly improved. In addition, since it has an almost solid structure, it has sufficient rigidity and is suitable for high-load calenders made of rubber or hard PVC.Although the material cost is relatively high, it has been increasingly used in recent years as product precision has become more sophisticated. has been done. However, such drilled rolls have the disadvantage that their weight increases, which increases the starting and stopping torque of the rolls.

A calender roll as shown in FIG. 3, which is a compromise between the hollow roll system and the drilled roll system, is also known in consideration of the above-mentioned drawbacks of the rolls.
In the roll shown in FIG. 3, a heating medium passage 7 is formed in the roll 6 to improve the heat efficiency of the roll, and the inside of the roll is hollow to reduce the weight. but,
In this roll, a heat medium is sent to a heat medium passage from an injection pipe 9 provided in one roll hollow chamber 8A, and a siphon pipe is sent from the other roll hollow chamber 8C separated from the roll hollow chamber 8A by a partition plate 8B. 10 so that the hollow chamber 8
The A side tends to be heated to a higher temperature than the hollow chamber 8C side, and a temperature gradient tends to occur in the axial direction (horizontal direction) of the roll surface length, and this is particularly noticeable in the case of steam heating.

In addition, in this type of roll having a heat medium passage near the roll surface, fluid such as air or oil is generally used to improve the roll temperature control function. However, since the roll shown in Fig. 3 has a hollow structure, fluid fills the roll hollow chambers 8A and 8C during use, which increases the weight of the roll and causes an adverse effect when starting and stopping. Since it stays in the roll hollow chamber, the roll temperature control effect itself decreases. Furthermore, when a high boiling point high temperature oil is used as the heating fluid so that it can be easily used at low pressure, deterioration of the oil is accelerated due to retention in the roll hollow chamber at high temperatures. On the other hand, when using water, which has a large specific heat and is effective as a heat medium, the pressure must be increased in consideration of the heating temperature, and it falls under the legal pressure vessel category, so it must be handled strictly. This requires frequent maintenance and operation.

An object of the present invention is to eliminate the drawbacks of the prior art and provide a lightweight calender roll structure with excellent thermal properties.

The present invention provides a roll outer cylinder having a heat medium passage for heating the roll bored near the surface inside the roll;
A heat medium supply for supplying and discharging a heat medium to and from the heat medium path for heating the rolls through an end wall portion that hermetically supports each roll end face of the roll outer cylinder and a center hole provided in the end wall portion. In the calender roll structure having a drainage passage, tube end openings provided along the axial direction inside the roll outer cylinder are connected and communicated with openings on the inside of the roll in each of the center holes to drain the heat. A hollow tube forming a medium supply exhaust passage, a heating medium passage for heating the roll in the roll outer cylinder, which is bored in the radial direction in each of the end wall portions, and the center hole and the hollow tube. A radial heat medium passage that communicates with the formed heat medium supply/discharge passage, and a space provided inside the roll outer cylinder so as to be isolated from each of the heat medium passages and communicated with the atmosphere. It is characterized by the presence of

Embodiments of the present invention will be described in detail below based on the drawings.

FIG. 4 shows a longitudinal section of a calender roll as an embodiment of the present invention.

Both end surfaces of the hollow roll outer cylinder 11 are the left and right bearing parts 1.
The rollers 2A and 12B are hermetically supported by roll side walls 13 and 14 as end wall portions integrally provided, respectively.

Center holes 15 and 16 are formed through each bearing portion and the roll side wall integral therewith, and a hollow tube 17 provided along the axial direction inside the roll is centered at each tube end opening. The holes 15 and 16 are joined and communicated with the openings of the holes 15 and 16 toward the inside of the roll, respectively, to form a heat medium supply and discharge passage 18 .

On the other hand, in the vicinity of the surface of the roll outer cylinder 11, there is a known heat medium passage for heating the roll, ie, a drilled heat medium passage 19 of the type shown in FIG. 2 or 3, for example.
A large number of holes are provided, and the heat medium is shown along the flow path direction shown by the arrow in the roll outer cylinder 11. As shown in the figure, each drilled heat medium passage 19 is formed by connecting three passages arranged in parallel at intervals in the roll circumferential direction in series inside the roll outer cylinder 11. A large number of them are arranged along the circumferential surface of the roll so as to average out the temperature distribution on the roll surface during heating.

Radial heating medium passages 2 are provided in the roll side walls 13 and 14.
1 and 22 are installed through each other, one end of each heat medium passage 21 and 22 opens into the center hole 15 and 16, respectively, and the other end opens into the drilled heat medium passage 19 in the roll outer cylinder 11. The heat medium supply/discharge passage 18 and the drilled heat medium passage 19 are connected to the inlet and outlet of the drilled heat medium passage 19, respectively, to communicate with each other.

Furthermore, the inside of the roll outer cylinder 11 is surrounded by a hollow tube 17 of the roll outer cylinder 11, the roll side walls 13, 14, and these heat medium passages 18, 19 and 21, 22. A space 20 is formed isolated from the air and communicated with the atmosphere through an air hole 23. Others in the figure, 24,
A supply and discharge pipe 25 is supported by a rotary joint 26 and is used to supply a heat medium to the hollow pipe 17. 27 is a seal ring attached to the hollow tube 17, and 28 is an end plate that seals the end of the roll shaft.

When a heating medium is supplied to the calender roll having such a structure to heat the roll surface, the heating medium is supplied from the supply pipe 24 and sent from the center hole 16 to the hollow tube 17, and the heating medium is The heat medium is sent from the exhaust passage 18 to the inlet of each drilled heat medium passage 19 in the roll outer cylinder 11 via the radial heat medium passage 21 in one roll side wall 13 . The heating medium is connected to each drilled heating medium passage 19.
The three inner passages are sequentially bent to heat the surface of the roll outer cylinder 11, and then returned to the center hole 16 via the radial heating medium passage 22 in the other roll side wall 14 and discharged from the discharge pipe 25 to the outside. is discharged. End plates 28 and 29 provided at both ends of the roll prevent the heat medium in the heat medium supply/discharge passage 18 from flowing out, and a seal link 27 provided in the hollow tube 17 prevents the heat medium in the heat medium supply/discharge passage 18 from flowing out. The heat medium in the passage 18 is introduced into the radial heat medium passage 21 without backflowing into the discharge side.

As described above, in this embodiment, since the heating method using the heating medium is basically the drilled heating medium passage 19 near the surface of the roll outer cylinder 11, the thermal characteristics of the roll can be improved. Can be done. Particularly in this embodiment, the center holes 15 and 16 provided in the roll side walls 13 and 14 are connected by the center pipe 17 to form a heat medium supply and discharge passage 18, and this heat medium supply and discharge passage 18 is connected to the roll side wall. 13,
Since the heat medium passages 14 are directly connected to the drilled heat medium passages 19 in the roll outer cylinder 11 through the radial heat medium passages 21 and 22 extending through the heat medium passages 14, the flow cross-sectional area of all the heat medium passages is almost uniform. Therefore, there is no part where the heating medium accumulates, and problems such as increased weight and deterioration of the heating medium do not occur.

Furthermore, in this embodiment, since the space 20 isolated from the heat medium passages is formed inside the roll outer cylinder 11, the weight of the roll can be reduced. Here, the roll wall thickness is determined by the roll separation force required for the forming operation and the strength and rigidity of the drilled heating medium passages 19, but the hole diameter of the drilled heating medium passages 19 is generally relatively small.
Since the dimensions are selected between 25 mm and 32 mm, it is possible to make the roll wall thickness sufficiently thin. This makes it possible to easily reduce the weight of the roll body of a calender roll with a roll diameter of over 1000 mm, for example, and to reduce the load on the drive device or main motor in this type of application that requires frequent startups and stops. can be reduced. Furthermore, by reducing the roll thickness, the heating time during temperature rise can be shortened, and power consumption can be reduced. The roll structure described above is not subject to legal regulations as a first class pressure vessel and is easy to handle.

In the embodiment shown in FIG. 4, the space 20 formed inside the roll has a circular cross section, but this space can have any shape. For example, as shown in FIG. The slit-shaped space 29 may be provided in such a manner as to maintain the balance of the roll weight. Further, as shown in FIG. 6, the roll side wall portion supporting the roll outer cylinder may be formed of an arm-shaped portion 30, and a radial heat medium passage 31 may be formed inside this arm.

As described above, according to the present invention, for example, a multiple of 3 (for example, 24, 27, etc.) drill holes through which the heat medium passes can be provided in the roll outer cylinder, and the drill holes can be provided as shown in FIGS. 4 to 6. As shown in the figure, since every three can be connected in series, the heat transfer fluid can make 1.5 reciprocations through the drill hole passage, during which time it can exchange heat with the material to be formed. Therefore, the following effects can be achieved.

(1) Since it is easy to set the heat medium flow rate to about 2 m/sec, which is ideal for heat transfer, a uniform temperature distribution can be obtained over the length of the roll surface, and the efficiency of heat exchange is much higher than that of the double pipe method. There is a difference.

(2) The heating medium passage is drilled approximately at the center of the thickness of the roll outer cylinder, which is a location where stress is least likely to be a problem, and the part that touches the side wall between adjacent passages has a rib effect, which improves strength. , which is advantageous in terms of rigidity.

(3) Heat transfer is easy because the heat transfer fluid flows very close to the material to be formed.

In addition, since the structure prevents the heating medium fluid from stagnation inside the roll, (1) the heating medium temperature can be efficiently controlled, allowing high-performance roll temperature adjustment.

(2) Since the moment (GD ² ) is small, it can be used for a wide range of applications, such as film and sheet production, which requires strict acceleration/deceleration and speed control for front and rear equipment, and roll stacking work, which requires frequent startup and stoppages. .

There are other effects.

Therefore, the structure of the calender roll can be made lightweight and have excellent thermal properties.

[Brief explanation of drawings]

1, 2, and 3 are longitudinal cross-sectional views showing the structures of various calender rolls in different aspects according to the prior art, FIG. 4 is a longitudinal cross-sectional view of an embodiment of the present invention, and FIG. A cross-sectional view of another embodiment. FIG. 6 is a cross-sectional view of yet another embodiment. 11... Roll outer cylinder, 13, 14... Roll side wall, 15, 16... Center hole, 17... Hollow tube, 1
8... Heat medium supply/discharge passage, 19... Heat medium passage for roll heating, 20... Space, 21, 22... Heat medium passage in the radial direction.

Claims (1)

[Claims] 1. A roll outer cylinder having a heat medium passage for heating the roll bored near the inner surface of the roll, an end wall portion that hermetically supports each roll end face of the roll outer cylinder, and a roll outer cylinder provided in the end wall portion. In the calender roll structure, the calender roll includes a heat medium supply and discharge passage for supplying and discharging a heat medium to and from the heat medium passage for heating the roll through a central hole formed in the roll. Hollow tubes that are joined and communicated with openings on the inner side of the roll of each center hole at tube end openings to form the heat medium supply and exhaust passages; a radial heating medium passage that communicates a heating medium passage for roll heating reciprocatingly drilled in the roll outer cylinder with a heating medium supply/discharge passage formed by the center hole and the hollow tube; A calender roll structure comprising: a space provided inside the roll outer cylinder and isolated from each of the heat medium passages and communicated with the atmosphere.